/Engine/Source/Runtime/Engine/Classes/Engine/Canvas.h
Calculates the horizontal and vertical size of a given string. This is used for clipped text as it does not take wrapping into account.
void TextSize ( const [UFont](API\Runtime\Engine\Engine\UFont) * InFont, const [FString](API\Runtime\Core\Containers\FString) & InText, double & XL, double & YL, double ScaleX, double ScaleY )